Circuit interrupter



' Dec. 25, 1945. c. L. scHucK CIRCUIT INTERRUPTER Fii'ed Dec. 21, 1942 Inventor: Carl L. Schuck, by W 6: 1W His Attorney.

Patented Dec. 25, 1945 CIRCUIT INTERRUPTER Carl L. Schuck, Philadelphia, Pa., assignor to General Electric Company, a corporation of New York Application December 21, 1942, Serial No. 469,628

Claims.

My invention relates to electric circuit interrupters and more particularly to improvements in circuit interrupters which are ordinarily mounted in a more or less inaccessible place and are adapted to be operated by a switch stick or similar operating means.

Circuit interrupting devices of the type referred to above often comprise a high voltage fuse device, such for example, as is disclosed in Rankin Patent 2,188,816 in which a plurality of relatively fine fuse wires are connected in parallel and mounted in a container which is filled with an inert granular arc extinguishing material. In order that such a fuse device may also operate as a disconnecting switch, the fuse device is pivotally mounted at one end and adapted to be latched in the closed circuit position by suitable latching means associated with the other end. Such a high voltage fuse device must be readily removable for both inspection and renewal and in the case of renewal it is desirable that the device replaced contains as little as possible additional equipment besides the fusible element. Accordingly, as is disclosed in United States Letters Patent 2,269,992 granted January 13, 1942, and assigned to the same assignee as the present application, such fuse devices mounted for switching purposes comprise a container with a ferrule mounted at each end thereof. A suitable hinge member is clamped to the lower or pivotally mounted end of the fuse or switching member and a suitable operating member such as an eye is mounted on the upper ferrule. In connection with the operating member such as the switch eye, it is desirable that this arrangement be constructed as simply as possible and also that the construction be both compact and economical. Furthermore, this operating means such as the switch eye must not interfere with the electrical contact made between the upper end of the fuse device and an external electrical circuit.

Accordingly it is an object of my invention to provide a new and improved circuit interrupter of the fuse type capable of being operated as a disconnecting switch, which is of a simple, compact and economical construction.

It is another object of my invention to provide a new and improved eye and clamp construction for operating a disconnecting switch embodying a fuse.

Further objects and advantages of my invention will become apparent as the following description proceeds and the features which characterize my invention will be pointed out with particularity in the claims annexed to and forming a part of this specification.

For a better understanding of my invention, reference may be had to the accompanying drawing in which Fig. 1 shows a side elevational view of a form of disconnecting switch device or circuit interrupter embodying my invention; Fig. 2 is a top view of a portion of the device shown in Fig. 1; Fig. 3 is a front view of the upper portion of the device of Fig. 1; and Fig. 4 is an enlarged perspective view of a portion of the device of Fig. 1 illustrating a modification of my invention.

As will be evident from the ensuing description, various features of the present invention are subject to modification and are suitable for employment in other forms of switch devices; hence the embodiment shown in the drawing is for the purpose of illustration only. In this embodiment the fuse support includes two insulators l0 and H disposed in spaced relationship and bolted or otherwise secured at one end to a suitable base not shown. On the other end of the upper insulator 10 there is supported a terminal and contact assembly including a terminal plate l2, having an upwardly projecting extension to which electric line conductors or leads such as 13 may be sevide a U-shaped contact member.

cured thereto as by clamping devices I4. Projecting perpendicularly from terminal plate 12 is a block IE to which a pair of generally L-shaped spring contact clips I6 are bolted as at I! to pro- A suitable U-shaped backing member I3 is provided to insure adequate contact pressure of spring clips 16 against fuse ferrule 25. The spring clips iii are provided with a corrugated portion so as to make line contact with a cylindrical ferrule of a conducting means such as a fuse device to be described hereinafter.

On the other end of lower insulator l I there is mounted a terminal plate l9 which similarly to terminal plate I 2, has an extension to which line conductors or leads, such as 20 may be secured by clamping devices such as 2|. The upper part of terminal plate I9 is adapted to serve as a hinge support and has a pair of integrally formed bracket arms 22 disposed in horizontal spaced relationship. Extending horizontally between the bracket arms is a suitable hinge pin 23.

The present invention may be embodied to advantage in various forms of switching elements or blades and it is not intended therefore that the invention be limited to any one particular form of switching element or blade. However, the invention is especially suited for use in connection with switching elements embodying fuse devices having cases constructed of glass, porcelain or other frangible material. Such a device is indicated at 24 on the drawing and is preferably of the form disclosed in the above mentioned Rankin patent. Fuse devices of the form shown in the Rankin patent are of considerable size and weight particularly when designed for high current interrupting ratings. They include a fusible element, and insulating supports therefor embedded in a body of sand or granular quartz which is contained in a tubular glass housing. Opposite ends of the glass housing are closed by metallic terminal ferrules such as 25 and 25 respectively which serve for connectingthefuseunit into an electric circuit. Such a fusemay be mounted incontact clips and held in a stationary position or it may be pivotally mounted to operate as a disconnecting switch. My invention is particularly concerned with an arrangement whereby such a fuse device which may be used in connection with a variety of different forms of mountings, can be readily operated as a disconnectingswitch. For mounting the fuse device 24 on the .previously described switching support, appropriate ttings are applied on the upper and lower ends respectively of the fuse device. The lower fitting comprises a metallic ring 21 clamped on the lower terminal ferrule 25 by means ofbolts 28. This ring 2? has a rearwardly extending portion defining a hook 23 for cooperatively fitting over the hinge pin 23 and supporting the fuse device thereon. As is disclosed and claimed in a copending application Serial No.1394,312 filed May .201, 1941, on behalf of Virgil L, Mares and assigned to thesame assignee as the present application,- now Patent 2,348,015, the hook 29 is so shaped as regards the spacing between the back surface of terminal plate 19 and the hinge pin 23 that the fuse device may be removed and attached to the support only in the wide open position thereof. As is further described and claimed in the above mentioned copending application, a suitable leaf spring or the like is mounted between bracket arms 22 to engage hook-shaped member 29 so as to insure good electrical connection between terminal plate I 9 and metallic contact ring '21.

.The fitting for the upper ferrule 25 of thefuse device 24 with which my invention isparticularly concerned comprises a C-shaped clamp 38 having jaw portions 3| of curvilinear construction so as. to readily engage the cylindrical ferrule 25. The C-shaped clamp 3i] as shown in Fig. 1, has integrally formed therewith a switch eye '32 which may be engaged by a suitable switch stick or the like. A suitable clamping bolt 33 passes through openings in the jaws 3! of clamp 30 and engages a threaded portion 35 so that the clamp 56 may be firmly attached to the upper terminal 25 of fuse device 24.

By using the C-shaped clamp construction the ferrule 25 may be made considerably shorterthan might otherwise be necessary and consequently save space which is at a premium in connection with disconnecting devices of this kind. The C- shaped clamp is adapted to firmly engage upper ferrule 25 without in any wayinterfering with the contact between fuse clips l6 and ferrule 25 as is clearly shown in Fig. 2 of the drawing. As-a matter of fact, with my new and improved construction it is merely necessary to design the ferrule 25 of a size which willgivethe necessary current carrying ability at the contacting points with spring clips 16 and C-shaped-clamp 30 can be readily attached thereto without in any way interfering with this current carrying ability as contrasted with prior art arrangements where the ferrule had to be designed sufficiently long to also accommodate a suitable fitting for supporting the operating eye.

The c-shaped clamp30 whose jaws 3| are capable of being tightened against the fuse ferrule 25 by turning screw or bolt 33 is preferably made of bronze or malleable iron and is provided with a reduced cross section 3!? at the top thereof which permits tightening and. loosening of the clamp without stressing the metal at this point and also without requiring too much tightening force, Also by using the C-shaped construction there is an open space between the closed end of the C and the upper surface of the ferrule 25. Usually the upper surface of this ferrule has inscribed thereon certain indicia such as is indicated at 36 in the drawing giving information with regard to the size and rating of the fuse device. This indicia. may be read with my improved construction without removing the clamp andeye which is a further advantage in addition to that described above whereby the fuse clip Hi can engage the ferrule 25 along its entire length.

In Fig. 4 I have illustrated amodification of the C-shaped clamp in which the eye is constructed separately from the clamp. The corresponding parts of Fig. 4 are designated by the same refer ence numerals as in Figs. 1, 2, and 3. Although .it is felt that the integral construction illustrated in Fig. 1 may be preferable for many casesgnevertheless situations may arise where it might be more desirbale to have the C-shaped clamp "30 and the eye 32 as separate parts as indicated in Fig. 4.

The operation of the switching device describe above will be obvious to those skilled in the art and it will be apparent that I have provided an upper fuse fitting which is simple, compact and economical and has many advantages over'prior art constructions.

While I have shown and described a particular embodiment of my invention, I do not desire my invention to be limited to the construction shown and described for it will of course be obvious that changes may be made without departing from my invention. I, therefore, aim in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of; my invention. p

What I claim as new and desire to secure by Letters Patent of the United States is:

1. In combination with a fuse comprising-a casing, a ferrul at each end thereof, a pair ofstationary terminal members, means electrically connected to one of said ferrules for electrically connecting said one ferrule and one of said ter-' to said other ferrule without in any way..interfering with the contact between said ferrule and.

said U-shaped contact member,

2. In combination with a fuse comprising a.-

casing, a ferrule at each end thereof, aipair'iof stationary terminal members, meanseIectrical-ly, connected to one of said ferrules for electrically; connecting said one ferrule and one of said ter minal members, said other terminal member comprising a U-shapedspring like contactmember for engaging said other ferrule along ,sub-

stantially the entire length thereof at diametri cally opposed areas on said ferrule, and a C- shaped clamp having a portion of reduced crosssection to permit tightening and loosening of the clamp without substantially stressing the metal at said point of reduced cross-section, an operating eye, and means for attaching said operating eye to said clamp and said clamp to said other ferrule at diametrically opposed areas on said ferrule displaced by substantially 90 from the areas of said ferrule engaged by said U- shaped contact member thereby in no way interfering with the contact between said ferrule and said U-shaped contact member.

3. In combination with a fuse comprising a casing, a ferrule at each end thereof, a pair of stationary terminal members, means electrically connected to one of said ferrules for electrically connecting said one ferrule and one of said terminal members, said other terminal member comprising a U-shaped spring like contact member for engaging said other ferrule along substantially the entire length thereof at diametrically opposed areas on said ferrule, and a C- shaped clamp having a portion of reduced crosssection to permit tightening and loosening of the clamp without substantially stressing the metal at said point of reduced cross-section, an operating eye formed as an integral part of said clamp, and means for attaching said clamp to said other ferrule at diametrically opposed areas on said ferrule displaced by substantially 90 from the areas of said ferrule engaged by said U-shaped contact member thereby in on way interfering with the contact between said ferrule and said U -shaped contact member.

4. In an electric switching device of the class wherein a conducting member provided with a ferrule at either end thereof is connected between two electrical terminals at least one of which is a U-shaped spring-like contact member for engaging substantially all of the length of one of said ferrules which ferrule is provided with suitable indicia on the end, the combination with said ferrule having the indicia at the end thereof of a C-shaped clamp including an operating eye, and means for clamping said clamp to said ferrule with the ends of said C-shaped clamp between said U-shaped contact so as in no way to interfere with the contact between said U-shaped contact member and said ferrule, said C-shaped clamp having a reduced portion substantially at the center of the C so as to permit exposure of the end ,of said ferrule having indicia thereon.

5. In combination with conducting means including a ferrule at each end thereof, a pair of terminal members, means electrically connected to one of said ferrules for electrically connecting said one ferrule and one of said terminal members, said other terminal member comprising a U-shaped spring-like contact member for engaging said other ferrule along substantially the entire length thereof at diametrically opposed areas on said ferrule, and a C-shaped clamp including an operating eye adapted to be clamped to said other ferrule at diametrically opposed areas on said ferrule displaced by substantially 90 from the areas of said ferrule engaged by said U-shaped contact member thereby in no way interfering with the contact between said ferrule and said U-shaped contact member.

CARL L. SCHUCK. 

